I'm building a regulated PS for a military radio, and decided to model a simple power supply in a circuit simulator w/ LM317 regulator and 2N3055 pass transistors. I have a Mac, and found EasyAda, and this was difficult as most of the parts didn't have models, and it kept crashing. Same for PartSim; I had to choose from their product line.

I then tried MultiSim online beta, which was intuitive, easy to draw, and get running. I was able to run and analyze the circuit, do what-if scenarios, etc. However, the extensive parts database seems only available if I buy the desktop version, very expensive (I'm neither a professional nor a student) and you have to buy the windows license, so it wasn't clear if the additional features would be available in the online version.

I tried LT Spice, and spent an hour just trying to figure out how to draw a signal source and RC circuit. Extremely cumbersome-it feels like software designed 25 years ago for a DOS machine.

So far MultiSim online is the best I've found, I spend less time drawing and more time analyzing and tweaking.

Are you aware of any other circuit simulator products for the experimenter?

The only one I've used is LTSpice, and I found it really easy to use so I'm surprised you had trouble with it. I'd give it another shot. Since it's a free download, there are no restrictions on what you can do, how big of a circuit, etc. Also it has a lot of user support out there on the internet. Maybe it's not the best interface, but the other points I just made more than make up for it.

Yes, LT Spice is also the only one I've seen people mention...so I was surprised too. I'l give it another shot...and see if there's a tutorial or something - or maybe I downloaded the wrong version or something. cheers

The best and most user friendly Spice based simulator I'veused is 'Microcap'. Its been around for ages. Entering a schematicis about as simple as it gets. There is some learning curve insetting up the simulations but several good examples are includedto help. It was available as freeware.

I too found LTSpice a PITA to use and didn't get very far with it.If it was a tool I'd use often I'd certainly put in the effort to learn it.Steve

_________________'cell phones and the internet are tools, not a lifestyle'

Many years ago I bought and used Electronics Workbench. I see they still have a website and offer a free Academic download of their software. It looks similar to what I remember but who knows what might have changed over the years.

Go from circuit simulation to PCB layout to BOM. Powered by NI, MultiSIM BLUE allows you to scheme, simulate, PCB layout, BOM and all in one integrated tool. Compare all the rest. No other FREE tool gives you this level of integration. jimmie

I will have to try some of the alternative circuit simulators mentioned above. However, I must admit to being pessimistic about whether or not they will meet my needs. I would rather hope that someone here would write one.... or perhaps point me to one that has the features I want.

I have tried LTspice (too steep a learning curve for me) and QUCS (utterly frustrating trying to extract information) and found both severely wanting.

Here are my chief criticisms:

There doesn't seem to be a simulator with a virtual oscilloscope, voltmeter, signal generator, ammeter, etc. Yes, I know that some simulators APPEAR to have these things, but in reality, they don't. Tied up with this is the net list architecture of most simulators. I want a simulator that will allow me to do the same things I can do on my bench. For example, I can remove a resistor from my parts bin, set it on the bench, and connect a volt meter across it. (There's no reason why I would want to do this, but I could.) The voltmeter will, of course, read zero. Now, take a single resistor, place it in a simulator schematic and connect a virtual voltmeter across it. You won't get zero.... you get a stream of error messages. I don't want a simulator that guesses what I want and adds nodes or anything else. I want it to simulate exactly what I have drawn. I want it to do this by allowing me to place test gear anywhere I want and display the results. If I have an incomplete series circuit, a volt meter ought to read zero or the supply voltage, depending on where I hook it up, but it ought to read... not display error messages.... especially generic unhelpful ones as QUCS does.

Secondly, I would like a simulator that is not so precise. Once I get a circuit that sort of works, then I can tailor it.... but in the meanwhile, I do not want to be bogged down in detail. For example: In every simulator I have run across so far, you cannot insert a transformer with a specific turns ratio and let it go at that. You have to define two inductors, specify the wire size, the degree of coupling, core losses, etc. just to get a transformer. I usually design my power supplies with overkill and size transformers with a rule of thumb. So, I don't need or want to get bogged down in minutia when all I want is a generic transformer!

I have used the Duncan amps power supply simulator, but it is not flexible enough. I know how to size diodes.... and I want a generic diode that I can use because I am concerned about other things, such as ripple at a specific output current. Unfortunately, the simulator doesn't allow for generic diodes and so one has to go into the data base and find a diode and edit its parameters to huge values so that one can get on with the design. Then, too, I once wanted an unusual topology and the simulator did not allow me to enter it.

Last but not least, I would like to find a simulator that has a large tube data base so I can design tube circuits.

Oh, yes.... most of the time, I don't need transient analysis... only steady state.

So, any simulators like that out there? If not, anyone care to volunteer to write one?